In recent years, proposal has been made to form an antenna element with a transparent conductive material formed on a non-conductive transparent film as an antenna apparatus that can be attached to glass of vehicles, stores, or offices, for example, and that does not impair the view and design. The transparent conductive material formed on the transparent film cannot be connected by soldering due to its low heat resistance. Therefore, a power feeding structure between a transparent conductive material and a power feed line, a metal conductor, is under consideration.
As an example of such a power feeding structure other than soldering, the antenna apparatus disclosed in Patent Literature 1 has been proposed, for example. FIG. 1 shows a configuration of the antenna apparatus disclosed in Patent Literature 1. FIG. 1A is a plan view showing a state in which antenna body 10 and connecting apparatus 11 and power feed line 12 are divided into two, and FIG. 1B is a cross sectional view of antenna body 10 and connecting apparatus 11 that are mounted on window glass 17.
Antenna body 10 is configured such that antenna element 14 is formed on antenna element holding sheet 13, and connection terminals 15a and 15b of the antenna element are provided. Connecting apparatus 11 is provided with wiring substrate 18 in which a low-noise amplifier, for example, is mounted, and one side of wiring substrate 18 is connected to power feed line 12 and the other side of wiring substrate 18 is connected to connection terminals 16a and 16b of connection apparatus 11. Connection terminals 16a and 16b of connecting apparatus 11 are formed with an elastic conductive member and are formed in a spring structure.
Connection terminals 15a and 15b of antenna body 10 and connection terminals 16a and 16b of connecting apparatus 11 are arranged on hard window glass 17 such that connection terminals 15a and 15b and connection terminals 16a and 16b overlap, and are fixed on window glass 17 using adhesive, for example. By this means, connection terminals 16a and 16b of connecting apparatus 11 are pressed by the spring structure and contact physically, leading to a conduction state.
Further, as another example of a power feeding structure, the antenna apparatus disclosed in Patent Literature 2 has been proposed, for example. FIG. 2 shows a configuration of the antenna apparatus disclosed in Patent Literature 2. Antenna apparatus 20 is configured such that antenna pattern 22 formed on film 21 and power feed line 23 are sandwiched by hard cover 25, hard front cover plate 26, and back cover plate 27, via power feed terminal plate 24, and are pressed together by screw 28 to be electrically conducted.